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Det. 22, 1925.

- A. E. HANDY ET AL ,SAFETY DEVICE FOR EscALAToRs Filed Aug. 30, 1922 2 Sheets-Sheet 1 n A l A. A I

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Dec. 22,1925. l 1,566,475

A. E. HANDY ET AL K SAFETY DEVICE FOR ESCALATORS Filed Aug. 30. 1922 2 Sheets-sneer 2 PatentedY Dec.. 22, 1925.

UNiTED *STATES1 1,566,475 PATENT oFFl-cs. f

AUMTHIUR E. HANDY, OF NEW YORK, AND SAMUEL Gr. MARGLES, F BROOKLYN NEW.' YORK, ASSIGNORS TO OTIS ELEVATOR COMPANY, OF JERSEY CITY, NEW' JERSEY,

A. CORPORATION 0F NEW JERSEY.

SAFETY DEVICE ronM EscALA'roRs.

Application led August 30, 1922'. Serial No. 585,956.

Jo all lwhom it may concern:

Be it known that we, ARTHUR E. HANDY, a citizen of the United States. residing at New York, county of New York, State of New York, and SAMUEL G. Manonns, a citizen oit the United States, residing in Brooklyn. in the county of Kings and State of New ."llfork, have invented a new and useful Inuk wiprovenlent in Safety Devices for Escalator-s,

of which the following is a specification.

'Our invention relates to inclined endless conveyers` more particularly of the step type commonly known as escalators. Essentially the invention consists in the provision of a safety device such -as an emergency brake tor controlling the escalator to stop it when certain undesirable conditions arise during the operation of the same.

The invention consists in the apparatus hereinafter described andillustrated in the accompanying dra-wing in which:

Figure 1 is a side elevation of an end portion of an escalator.

Figure 2 illustrates the emergency brakel the escalator driving sprocket shown in part.

Figure 4 illustrates a sectional view of Figure 3 on the lins 4 4.

Figure illustrates diagrammatically a system of circuits that may be used to describe the operation of our invention.

lLike reference characters denote similar parts in all of the gures.

Reference being had to Figure 1, an escalator of which only a part is shown comprises a series of steps A which form an endless movable vplatform or surface connecting diierent floor levels (not shown). Ea'ch step has a pair of rear wheels 1, and a pair ot front wheels 2. and are adapted to travel respectively on suitable track rails such as 3 and 4. There is provided for the purpose of driving the steps. an endless chain 5, arranged on a center line coinciding with the center of a sprocket 6. A similar chain 5 on the escalators other side is arranged in the same manner with a similar sprocket 6 also onthe escalators other side. The chain comprises a series of links pivotally connected with the front wheel axles of the steps to form the endless chain 5. The sprockets are constructed with cut-out portions such as 7, to accommodate the front step wheels 2, and cut-out portions such as 8, to accommodate the chain. A driving sprocket 9 fastened 'to the shaft of the sprocket 6 is vadapted to drive the escalator and may be driven by any suitable source of power, for instance, by an electric motor M, as shown.

Coming now to the particular part of the present invention, an emergency brake B ot the/multiple disc type is mounted on the i driving shaft together with the driving sprocket. 9 and the sprockets 6, and isadapted to rotate with them. Referring to Figures 3 and 4:, the brake comprises a movable member 10 on the outer rim of which there are cams 11 and teeth 12, and in dierent planes from each other. To the inside of the member 10 there is keyed by keys 13,'

that are held in place by screws 14 in the member and screwed to its key, a circular disc member 15. 'To another movable member 16 there is keyed by keys`17, that are held in place by screws 18 in the driving circular disc member 19. To the member 16 there is fastened bolts 20 which also pass through the driving sprocket 9. Each bolt 2O has a spring 21 thereon, the bolts and their springs pulling the member 16 and the 'driving sprocket 9 together. Since the member 16 is pulled to the sprocket 9 by lthe springs 21 through their bolts 20, the meurber 16 in turn jams, so to speak, the members 10, and 19 and four wooden circular, discs 22 between them, also to the driving` sprocket 9. The frictional engagement obtained by the wooden discs 22 causes the emergency brake, of. which they' are a part,

to turn with the driving sprocket 9 when itl .sprocket 9 and screwed into its key, another los the arm when the escalator is running normal. When the escalator. overspeeds in either direction the impulse of `the cams on the roller is more than the weight will' balance and the roller therefore leaves the cam.

When the overspeed reaches a predetermined amount the governor arm 23 and its roller' cient amount to' 26 is thrown out a sutli cause a finger 28 formed at the upper end of the arm 23 to contact with a bolt 29 carried by an arm 30loosely journaled at 31 to a switch D and trip a trigger 32 of the switch y hinged at 33. It will be noted -tliat ythe trigger 32 has a pro'- jection 321 extending downwardly and normally resting upon a projection 301 on arm 30. Upon movement of the arm 30 the projection 301 passes from beneath the projection 321 and allows the trigger 32 to drop` which in dropping breaks contact by a pair of contact fingers 34 fastened to the trigger with a pair of electrical contacts 35 in the switch, which will cause the escalator driving motor to be stopped as will be se'en hereinafter. i

Still referring. to Figure 2, an electromagnet E, having a winding 36, is fastened to the esclator frame work 25, and is adapted to operate apawl 37, the pawl being loosely journaled to a movable core 38 of the electromagnet and also hinged at 39 to the escalator frame work 25. In the Figure 2 the electromagnet is shown as energized and by itsl movable core 38 is holding the pawl 37 free from the teeth 12 on the member 10 of the brake which it is adapted to engage when the electroinagnet is deenergized as will be seen hereinafter. The pawl, when held awa-y from engagement with the vteeth 12, holds closed a switch F fastened to the frame work -of the escalator by a trigger 41 of the switch resting on the pawl. A pair of contact n- -gers 42 fastened to the trigger engages a pair of electrical contacts 43 when the switch is in a closed position.

Referring to vFigure 5, the operation of the apparatus is as follows: Assuming that the escalator overspeeds .in an ascending direction, which in the presentiiivention is in a direction to the observers right, to apredetermined amount which will cause the governor Cto be moved aside bythe cams 11 on the brake member 10 and i -the winding 44 of an electromagnet poten'- tial switch G which, when it opens, opens 'i the supply circuit to the escalator driving motor and causes its brake B to beapplied to stop it.

. The brake B as diagrammatically shown comprises a brake shoe '46 which is carried by core 47 and has a spring 48 for applying it and a solenoid 49 for retracting the core 47 for releasing the brake. When the switch G is closed a circuit is made from the positive side of the source, by wire 50, through solenoid 49, and by wire 51. to the negative Side of the source, and when the switch'G is opened the solenoid is d'e-energized and the spring will apply the brake.

The present apparatus is adapted to operate when another undesirable condition occurs, namely the breaking of the escalator driving chain 45, whichmay cause a reversal of the escalator, at such a time and when the speed of the reverse direction of travel of the escalator reaches a predetermined value the governor will operate as before, the pawl 37 at this time when released will engage the teeth 12 on the member 10 holding the inember stopped, the frictional engagement of the brake, by its wooden discs 22, with the driving sprocket 9 will cause it to be slowed down and stopped. AAt the same time the .emergency brake B is applied so also is the brake B of the escalator driving motor applied to the motor to stop it.

In brief, if the escalator exceeds the speed designed for its proper normal operation due to high voltage or breaking of the driving chain, the .escalator will be automatically slowed down through theaction of the governor, and stop ed.

One skilled in the art may make obvious changes in the details and arrangement of parts without departing from the spirit and scope of our invention, -and .we wish therefore not to be limited tothe precise arrangement and details as are herein illustrated and described. What we claim as new and` desire to secure by Letters Patent of the United States is:

1. In combination with the driving mech- `anism for a conveyor, a brake drum coopengage said teeth for stopping the conveyor.

2. In combination with the driving mechanism for a conveyor, a brake drum operatively connected with said driving mecha- Y nism, means in the connection between said brake drum and driving mechanism adapted to yieldably resist relative rotation of the,

drum and driving mechanisinand'means adapted to engage and hold said drum whereby the driving mechanism may be brought toa stop.

3. In combination with the driving mechanism for a conveyor, a brake drum opera-V tively connected with said driving mechanism and provided with teeth, means in the l connection between said .brake druml and driving 'mechanism adapted to yieldingly resist rotation of the drum with respect to 'the driving mechanism, and a pawl member adapted to engage the teeth on the brake drum for holding it and thereby bring the driving mechanism to 'a stop.

4. In an electric poweroperated escalator, a device to control excessive speed of the escalator. said device comprising a switch adapted to be opened in case of excessive s eed of the escalator and effect the interruption of the driving power for the escalator, a part adapted to be operated by the'operation of the escalator to effect the opening of the switch in case of excessive speed of the escalator, a ratchet adapted to be operated by the operation of the escalator, a -stationary pawl adapted to be released to engage the ratchet, and an electromagnet to old the ilnawl out of engagement with the ratchet unti released in case of excessive speed of the escalator.

5. In the electric powerv operated inclined conveyer art, involving a brake for the conveyer, a safety device comprising a' awl and ratchet, a swltcli adapted to contro the engagement of the pawl with the ratchet and 'the driving power for the conveyer, cams,

and a governor adapted to be operated by the cams, said switch adapted to be o ned by said operation of the governor, an permit the pawl and ratchet to engage each other, and apply the brake to the conveyor.

6. In the electric power operated escalatorA art, an 4emergency brake comprising a rotatable multiple disc brake having a member with cams thereon, a governor adapted to be actuated by the cams on the said member in revolving, an electric switch adapted to be opened by the governor, an electromag- Anet adapted to be deenergized by the governor, and a pawl adapted to be actuated by ythe denergizing'ofthe electromagnt, and a adapted to be actuatedby the cams on the said member in revolving, an electric switch adapted to be o ened by the governor, an electromagnet adapted to be deenergized by the said switchl in opening, and a pawl adapted to be actuatedV by the deenergized` electromagnet, to engage the teeth on the said member to apply the emergency brake to stop the escalator, and a second switch adapted to be openedl by said pawl to open the circuit to the electric power for stopplng the escalator.

In testimony whereof, we` have signed our i names to this' specification.

ARTHUR E. HANDY. SAMUEL G. MARGLES. 

